#include<dos.h>
#include<conio.h>
#include<graphics.h>
#include<stdio.h>
#include<stdlib.h>

#define UP 72
#define LEFT 75
#define RIGHT 77
#define DOWN 80
#define ESC 1
#ifdef __cplusplus
     #define __CPPARGS ...
#else
     #define __CPPARGS
#endif
struct SnakeParts{
         int x;
         int y;
}box[50],target;
void snake(int ,int );
void initialize(int,int);
void interrupt (*prev)(__CPPARGS);
void interrupt our(__CPPARGS);
void snakeb();
int check();
void Rectangle(int ,int,int,int);
int
stop=0,blocks=4,direction=2,size=10,hit=1,snake_color=14,bk=7,target_color
=4;
int stage=1,speed=100,point=0;
void main(){
         int gd=DETECT,gm,x=100,y=100,i=0,j=0;
         char msg[50];
         initgraph(&gd,&gm,"");
         /*animation*/
         prev=getvect(9);
   /*        setcolor(bk);
         rectangle(0,0,639,479);
         setfillstyle(SOLID_FILL,bk);
         floodfill(250,250,bk);*/
         initialize(x,y);
         //getch();
         while (1){
                 /*setcolor(bk);
                 sprintf(msg,"POINT = %3d",point);
                 settextstyle(0,HORIZ_DIR,1);
                 outtextxy(550,100,msg); */
                 switch(direction){
                         case 0: j-=size;break;
                         case 1: j+=size;break;
                         case 2: i+=size;break;
                         case 3: i-=size;break;
                 }
                 setcolor(snake_color);
                 snake(x+i,y+j);//,x+15+i,y+15+j);
                 delay(speed);
                 setcolor(bk);
                 snakeb(/*x+i,y+j*/);//,x+15+i,y+15+j);
                 setvect(9,our);
                 if(stop==1){break;}
                 if(check()){break;}
                 if(hit==1){
                         hit=0;
                         target.x=size+size*random(25);
                         target.y=size+size*random(20);
                         setcolor(target_color);
                         setfillstyle(SOLID_FILL,target_color);
                         circle(target.x+size/2,target.y+size/2,size/2-1);
                         floodfill(target.x+size/2,target.y+size/2,target_color);
                 }
                 setfillstyle(SOLID_FILL,target_color);
                 setcolor(2);
                 circle(target.x+size/2,target.y+size/2,size/2-1);
                 floodfill(target.x+size/2,target.y+size/2,2);
                 /*setcolor(11);
                 sprintf(msg,"POINT = %3d",point);
                 settextstyle(0,HORIZ_DIR,1);
                 outtextxy(550,100,msg);*/
                 gotoxy(65,4);
                 printf("POINT = %3d",point);
                 //delay(3000);
                 //cleardevice();
         }
         closegraph();
}
void interrupt our(__CPPARGS){
         //if(inportb(0x60)==UP){
                 //i=0;j
          switch(inportb(0x60)){
                 case UP: if(direction==1)break;direction=0;break;
                 case DOWN: if(direction==0)break;direction=1;break;
                 case RIGHT: if(direction==3)break;direction=2;break;
                 case LEFT: if(direction==2)break;direction=3;break;
                 case 15:blocks++;break;
                 case ESC:  stop=1;break;
          }

          (*prev)();
}
void snake(int x1,int y1){//,int x2,int y2){
         int k=0;
         //if(getcolor()==15){
                 for(k=blocks-1;k>0;k--){
                         box[k].x=box[k-1].x;
                         box[k].y=box[k-1].y;
                 }
                 box[0].x=x1;
                 box[0].y=y1;
         //}
         //setfillstyle(SOLID_FILL,snake_color);
         for(k=0;k<blocks;k++){
                 Rectangle(box[k].x,box[k].y,box[k].x+size,box[k].y+size);
                 //floodfill(box[k].x+size/2,box[k].y+size/2,snake_color);
         }

}
void snakeb(){
         //setfillstyle(SOLID_FILL,bk);
         for(int k=0;k<blocks;k++){
                 Rectangle(box[k].x,box[k].y,box[k].x+size,box[k].y+size);
                 //floodfill(box[k].x+size/2,box[k].y+size/2,bk);
         }
}
void initialize(int x,int y){
         setcolor(bk);
         rectangle(0,0,639,479);
         setfillstyle(SOLID_FILL,bk);
         floodfill(250,250,bk);
         box[0].x=x;
         box[0].y=y;
         for(int i=1;i<blocks;i++){
                 box[i].x=x-size*i;
                 box[i].y=y;
         }
         /*for(int k=0;k<blocks;k++)
                 rectangle(box[k].x,box[k].y,box[k].x+15,box[k].y+15);*/
}
int check(){
         int i;
         char msg[50];

         if(!(box[0].x>=0 && box[0].x<=639 && box[0].y>=0 && box[0].y<=479)){
                 for( i=100;i<700;i+=100){
                 sound(i);
                 delay(100);
                 nosound();
                 }
                 sprintf(msg,"GAME OVER");
                 setcolor(4);
                 settextstyle(1,HORIZ_DIR,6);
                 outtextxy(150,200,msg);
                 delay(3000);
                 cleardevice();
                 return 1;
         }
         for( i=1;i<blocks;i++){
                 if(box[0].x==box[i].x && box[0].y==box[i].y){
                         sprintf(msg,"GAME OVER");
                         setcolor(4);
                         settextstyle(1,HORIZ_DIR,6);
                         outtextxy(150,200,msg);
                         delay(3000);
                         cleardevice();
                         return 1;
                 }
         }
         if(box[0].x==target.x && box[0].y==target.y){
                 //for( i=50;i<400;i+=50){
                 sound(700);
                 delay(100);
                 nosound();
                 //}
                 blocks++;
                 point++;
                 hit=1;
                 setcolor(bk);
                 //circle(target.x+size/2,target.y+size/2,size/2-1);
                 setfillstyle(SOLID_FILL,bk);
                 setcolor(bk);
                 circle(target.x+size/2,target.y+size/2,size/2-1);
                 floodfill(target.x+size/2,target.y+size/2,bk);
         }
         if(blocks==40){
                 stage++;
                 blocks=4;
                 sprintf(msg,"STAGE %d CLEARED",stage-1);
                 setcolor(4);
                 settextstyle(1,HORIZ_DIR,6);
                 outtextxy(150,200,msg);
                 delay(2000);
                 cleardevice();
                 initialize(100,100);
                 speed=100/stage;
         }
         return 0;
}
void Rectangle(int x1,int y1,int x2,int y2){
         for(int i=0;i<size/2;i++)
                 rectangle(x1+i,y1+i,x2-i,y2-i);
}

